Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Investments
Total fixed maturity securities, Available for sale, Cost or amortized cost	$ 5,856,432	$ 5,385,432
Fair value for fixed maturity securities - held to maturity, at amortized cost	0	163,136
Fair value for equity securities-available for sale, at cost	275,827	0
Other investments, amortized cost	$ 18,391	$ 38,230
SHAREHOLDERS' EQUITY
Common stock, par value	$ 1.00	$ 1.00
Common stock, shares authorized	250,000	250,000
Common stock, shares issued	125,114	122,720
Common stock, shares outstanding	100,928	104,101
Treasury stock	24,186	18,619